In order to optimize the efficiency of sunlight-absorbing devices to turn sunlight into electricity, it is important to be able to reliably and accurately track the motion of the sun across the sky with these devices, to ensure optimal reception of the sun's light.
The tracking or guide motion of a sunlight-absorbing device can be realized, for example, by moving the device around two axes, namely an azimuth axis and an elevation axis. In a standard design, movement around the elevation axis can be achieved by using two motors and gears at both ends of the guide system's housing along the elevation axis of the guide system.
Using two motors for one axis, however, not only is more expensive than, for example, just using one, but also the guide system becomes more complex and, therefore, more vulnerable to technical failure.
Alternatively, a further standard design makes use of a U-shaped element to transmit the torque exerted by a single elevation axis motor and gear at one end of the guide system's housing along the elevation axis to the other end. This design, however, is only suited to hold and move rather small and light sunlight-absorbing devices, which do not put too much torsion and load stress on the U-shaped torque transmitting element, which significantly can worsen the precision of the tracking.
In EP2063200A1, a two-axle drive system is described, wherein a single-drive motor/drive is used to hold and move a sunlight-absorbing surface around the elevation axis, wherein the surface is mounted directly to the shaft of the elevation axis drive. This design can lead to a disadvantageous distribution of load and torque within the system, in particular, for very large and heavy sunlight-absorbing surfaces or devices.
The objective technical problem to be solved can be stated as how to improve guide systems for holding and moving sunlight-absorbing devices, for example, Concentrated Photovoltaic (CPV) modules, in particular, with respect to stability, precision and efficiency.
The above-stated problem is solved by this disclosure by providing a guide system as described below.